Security cards are becoming an important information element in this high-tech world. Information is encoded in the form of magnetic signatures and/or optical signatures. The magnetic signatures can be found on either magnetic strips or imbedded within magnetic particles in the body of the card where the card is formed of a solid plastic body with magnetic particles uniformly distributed throughout the body. These cards include credit cards, debit cards, personal ID cards, security passes, and smart cards. The optical signatures are typically found on the surface of the cards in the form of pictorial images such as ID photos, company logos, and emblems. These cards are generally made from plastic resin materials such as polystyrenes, polyesters, polyurethanes, polyamides, PVC (poly-vinyl chloride), polycarbonates, PET (poly-ethylene terphthalate), polyolefins, and PEN (poly-ethylene napthalate). After these resins are plasticized, the plastic material tends to be soft, vulnerable to common mechanical wear and vulnerable to chemical attack. To minimize common mechanical wear, these plastic cards are treated with additional lubricants such as esters, stearates, silicones, polymeric silicones, paraffins, and siloxanes.
Because such cards are of plastic material and any added lubricant tends to have an organic base, they are still vulnerable to common mechanical wear, deterioration and chemical attack in everyday handling, storage, and as they are used in card readers. These problems result in a short lifetime of the plastic card in the loss of and/or distortion of the optical or security information and in many cases loss of encoded magnetic information. Additionally, since optical registrations are placed on the surface, they become susceptible to security tampering.
There is thus a need for improved protection and security which can be addressed by using an effective protective coating that is thin, hard, wearable, impervious to harsh environments. Coatings with such qualities are commonly thin films and are inorganic oxides such as Alumina, inorganic carbides such as Silicon Carbide and Titanium Carbide, inorganic nitrides, such as Silicon Nitride and Titanium Nitride or diamond like such as Diamond Like Carbon (DLC). These coatings, however, when applied as thin films under common standard vacuum processing temperatures and conditions become extremely incompatible with the plastic cards which have melting temperatures which are at or below the processing temperatures for such coatings.